This assessment of portable water quality was conducted to determine the physicochemical and biological characteristics in protected springs and borehole water of Kumi Town Council in Eastern Uganda. Protected springs in the Town council were studied, including Odello, Omulubin and Okwakel protected springs, as well as five boreholes that were functional out of the nine boreholes in Kumi Town Council; that is: Elgonia, Wiggins p/s, Kumi girls, Works and Omatenga Rd boreholes.
pH and temperature were measured in the field directly while iron, hardness, turbidity, nitrites, E-coli and T-coli were analyzed in the laboratory using the standard procedures for water sample analysis. The results showed borehole water was of better quality than the protected springs since most values of the parameters (E-coli, Total coli forms, Turbidity, and Hardness) of borehole water were within the WHO (2008) and UNBS (1994) permissible limits of drinking water.
The major contaminant in borehole water was Iron attributed to natural processes and Nitrites, which was attributed to human and animal fecal contamination in the water catchment areas. Generally, borehole water was of better quality for human consumption, and protected spring wells were contaminated with Total coliforms.
Inhalt
Abstract
INTRODUCTION
MATERIALS AND METHODS
RESULTS AND DISCUSSION
CONCLUSION AND RECOMMENDATIONS
References
Abstract
Assesment of portable Water quality in to determine the Physico-chemical and Biological characteristics in protected springs and Borehole water was conducted in Kumi Town Council. Protected springs in the Town council were studied this includes Odello, Omulubin and Okwakel protected springs and five boreholes that were functional out of the total of nine boreholes in Kumi Town Council that is; Elgonia, Wiggins p/s, Kumi girls, Works and Omatenga Rd Bore holes. pH and temperature were measured in the field directly while iron, hardness, turbidity, nitrites ,E-coli and T-coli were analyzed in the laboratory using the standard procedures for water sample analysis. The results showed borehole water was of better quality than the protected springs since most values of the parameters (E-coli, Total coli forms, Turbidity, and Hardness) of borehole water were within the WHO (2008) and UNBS (1994) permissible limits of drinking water. The major contaminant in borehole water was Iron attributed to natural processes and Nitrites which was attributed to human and animal faecal contamination in the water catchment areas. The highest mean value of E-coli bacteria in protected spring wells was (22.5±3.536)/100 mg/l at Okwakel (SW3) and the lowest was (0±0)/100 mg/l at Omulubin (SW2). The mean values of E-coli for boreholes were all at (0±0)/100 mg/l for all the five boreholes sampled. The highest value for Total coli forms in the protected spring wells was (18.5±2.121)/100 mg/l at Odello (SW1) and the lowest was (1.5±7.707) /100 mg/l at Okwakel (SW3). Generally, borehole water was of better quality for human consumption and protected spring wells contaminated with Total coliforms.
Key words: Contamination, Water quality, Hygiene, Impurities and Sanitation
INTRODUCTION
Every year, millions of the world’s poorest people die from preventable diseases, inadequate water supply and sanitation services (DFID, 1998). Hundreds of millions suffer from regular bouts of diarrhea or parasitic worm infections that ruin their lives (DFID ,1998).Women and children are the main victims, Burdened by the need to carry water containers long distances every day, they must also endure the indignity, shame and sickness that result from lack of hygienic sanitation. The impact of deficient water and sanitation services falls primarily on poor unreached by public services (DFID, 1998). People in rural and peri urban areas of developing countries pay excessively high prices to water vendors for meager water supplies. Their poverty is aggravated and their productivity impaired, while their sickness puts severe strains on health services and hospitals (DFID, 1998).
Water and sanitation services coverage remains a challenge in Africa. In the year 2000, approximately 36% of the population did not have access to a safe water supply and about 40% did not have access to sanitary facilities (WHO, 2001).The figures for African countries show greater disparities 50% of those in rural areas have no easy access to safe water compared with 14% in urban areas. As much as 52% of the rural population lacks sanitation, compared with 20% in urban areas. And these gaps are widening making a large number of the population to suffer from water and sanitation related illnesses of water born diseases, water arthropod, water washed and water related diseases of Malaria, Diarrhea, Cholera, Dysentery, and Bilhazia (WHO, 2001).
The Objectives of the study were to determine the physico-chemical, chemical and bacterial characteristics of portable protected spring and borehole water.
MATERIALS AND METHODS
Description of the study area
Kumi district is one of the districts in mother Teso located at about 315kms from Kampala town Uganda’s capital city in the eastern part of the country. Kumi District is bordered by Katakwi District to the north, Nakapiripirit District to the northeast, Bukedea District to the east, Pallisa District to the south, and Ngora District to the west. Kumi town is located approximately 54 kilometres (34 ml), by road, southeast of Soroti, the largest town in Teso sub-region. The coordinates of the district are: Latitude 01 30N and Longitude 33 57E.
Sample sites
Water samples were collected from Odelo, Omulubin and Okwangakel protected springs, Elgonia, Wiggins p/s, Kumi girls, Works and Matenga road bore holes. The water samples were then transported to Kumi district water office laboratory for analysis in an icebox at 4oC. The samples were then analyzed for physico-chemical, chemical and biological parameters.
Table 1: Description of the study sites for protected springs
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Table 2: Description of study sites for Boreholes
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Sample selection
The total number of protected springs in the town council were sampled and included Odello Spring well, Omulubin Spring well and Okwakel spring well as well as five boreholes that were functional out of the total of nine boreholes in Kumi town council (Elgonia BH, Wiggins p/s BH, Kumi girls BH, Works BH and Omatenga Rd BH).
Water sampling procedure, Sample preparation and laboratory analysis
Water samples were collected using 500ml polythene bottles for physico-chemical parameters and 300ml glass bottles for bacteriological parameters. Water was sampled from the protected springs and boreholes.
a) Bacteriological parameters
Before collecting water samples, the top of the outlet nozzles of the boreholes and protected springs was sterilized by burning them with a flame so as to kill all the pathogenic bacteria to minimize contamination. A sample was collected directly from the spout with a sterile container. This was collected from a position that equates to the draw off point.
b) Physico-chemical parameters
Sampling bottles were first washed with Nitric acid and double rinsed with de-ionized water. During sampling, sample bottles were rinsed with sampled water three times. Samples were taken by holding the bottle by its base and plunging it below the water surface. Then the bottle turned slowly upward and the mouth directed towards the current thus, avoiding contact with the spring.
3.6 Determinations of physico - chemical parameters
Variables which are indicators of portable water quality such as pH and temperature were determined directly on site using portable meters. Other parameters such as water hardness were determined in the laboratory using Palin test photometer. Use of Hardcol tablets NO1 and NO2, the tablets were crashed and dropped in 10mg/l test tube of water in order of 1 and 2 and the mixture left for 5mins, Then readings were taken at 570nm wave length in the Palintest Photometer. Two test tubes were used, one acted as a control experiment (Shanthi De silva and Ayomi, 2004).Turbidity was analysed using Turbidity tube where Water was poured in the tube while observing the x mark below the tube and if it disappeared that unit was recorded as the turbidity value for the water sample under analysis. It was measured in Naphthalene Turbidity Units (NTU).
3.7 Determination of the chemical parameters
Chemical elements that were analyzed for water quality include Iron and Nitrites following standard procedures for water analysis. All these parameters were determined photo electrically using the same method of Palin test (Photometer model 5000) the procedure for analysis for all parameters was the same at same wavelength of 520 nm for Iron and Nitrites, and different reagents used. For Nitrites, the Nitricol tablets NO1 was used. The tab was crashed and dropped in 10 mg/l test tube of water, mixed and left for 10 minutes then the readings were taken at 520 nm wave length in the Photometer where by two test tubes were used, one acted as a control experiment. Also in the analysis of Iron, Iron testing tablets NO1 and NO2 were crashed and dropped in 10 mg/l test tube of water in order of 1 and 2 mixed and left for 2 minutes and the readings were taken at 520 nm wavelengths in the photometer. Two test tubes were used, one acted as a control experiment.
3.8 Microbiological examination
Total coliforms and Feacal coliforms were determined in the laboratory using membrane filter (MF) technique (Kazinja , 2002). Three spatula of Broth-lauryl sulphate broth (food for bacteria) was mixed with 30 ml of water (distilled water). Absorbent pads were dispensed to sterilized Petri dishes and soaked with broth. The water sample was measured and filtered through a sterile membrane filter which retains all bacteria. The membrane was then transferred to the petri dishes containing M-FC media for feacal coliforms and M-TC for total coliform in duplicate and incubated at 37oC for total coliforms and 44oC for feacal coliforms for 24 hours to isolate indicators organisms from the water sample. The counts of bacteria were conducted to determine the number of bacteria per 100 mg/l and recorded.
RESULTS AND DISCUSSION
The level of Biological and physico-chemical parameters of portable water from protected springs and bore holes .
Table 3: Mean and standard deviation (SD) for Physico - chemical and Bacteriological parameters for protected springs and boreholes.
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Turbidity
The mean Turbidity values for protected springs ranged between (0±0) NTU at Omulubin and Odello and (8±1.414) NTU at okwakel (Table 3). Results showed that mean Turbidity values at Okwakel (8±1.414 NTU) was highest and was above the WHO (2008) guideline while Odello and Omulubin protected spring were within the WHO (2008) and UNBS (1994). The Turbidity of the water may be aesthetic and media for bacteriological growth.
The mean Turbidity value for all the Boreholes was (8±1.414) NTU at Elgonia, Wiggins p/s, Kumi girls, Works and Omatenga Rd boreholes were within the required water Turbidity limits as per the WHO (2008) and UNBS (1994). The results agree with the observations made by Emmanuel Bernard and Nurudeen Ayeni (2012).
pH
The pH limit is set so as to maximize the stability and minimize the corrosivity of the water, and for water that under goes treatment, it’s important to take note of pH readings so as to maximize the disinfection process. The standard set by WHO (2008) and UNBS (1994) guidelines of pH range is; 6.5-8.5. The mean pH ranges were between (5.65±0.071) at Omulubin and Okwakel and maximum mean pH of (5.85±0.071) at Odello protected spring (Table 3).The pH values for protected springs were slightly acidic.
Borehole mean pH values obtained from different sites were slightly acidic. The highest mean value of pH from the borehole site was (6.75±0.071) at Works borehole and the lowest mean pH value was (5.59±0.071) at Wiggins p/s borehole (Table 3). Generally all the pH values for the protected springs and boreholes were slightly acidic. Consumption of such acidic water could have adverse effects on the digestive and lymphatic systems of human. Acid water can also lead to corrosion of water could also lead to corrosion of copper pipes which could in turn, lead to copper poisoning. Copper contaminated water is responsible for health hazards such as abdominal pains, nausea, vomiting, diarrhea, headache, and dizziness (Shalom Nwodo Chinedu et al., 2011).
Iron
The mean Iron concentration value from the protected spring sites ranged between (0.12±0.014) mg/l at Odello and the lowest value was (0.155±0.007) mg/l at Omulubin (Table 3). The Iron concentration in all the three protected springs were above the WHO (2008) and UNBS (1994) guidelines.
The mean Iron concentrations for boreholes ranged between 0.36±0.014 mg/l at Elgonia and the lowest was 0.56±0.014 mg/l at Omatenga RD (Table 3). All the mean iron concentration values for boreholes from the lowest to the highest were far above the WHO (2008) and UNBS (1994). Suggesting that Iron concentration could be attributed to the nature of the parent rock and solubility potential of iron in water which depends on oxidation/reduction potential. It is noted that anaerobic groundwater may contain ferrous iron at concentrations of up to several mg/l without discoloration or turbidity in the water when directly pumped from a well. On exposure to the atmosphere, however, the ferrous iron oxidizes to ferric iron, giving an objectionable reddish-brown color to the water. Iron also promotes the growth of “iron bacteria,” which derive their energy from the oxidation of ferrous iron to ferric iron and in the process deposit a slimy coating on the piping (WHO, 2011).
Hardness
The highest mean value of Hardness was (15.5±2.121) mg/l at Okwakel and the lowest was (0±0) mg/l at Omulubin protected spring well (Table 3).The values from all the three sites were within the WHO (2008) and UNBS (1994) water guidelines. This may be attributed to the nature of the rocks in the area.
The mean values for boreholes had the highest Hardness as being (110.5±6.364) mg/l at Works and the lowest was (0±0) mg/l at Elgonia, Wiggins p/s and Kumi girls (Table 3). Although the Hardness may be high in Works (BH4), it’s far much below the WHO (2008) and UNBS (1994) allowable limits of (500 and 600) mg/l respectively. Generally, the protected springs and boreholes values indicate that the water in Kumi town council is not hard. These results are in agreement with finding by NDEFO et al., (2011) that, there was significant increase in the level of total Hardness of water sample from borehole sources when compared with the protected spring sources. Hardness caused by calcium and magnesium usually results in excessive soap consumption and subsequent “scum” formation (Emmanuel Bernard and Nurudeen Ayeni, 2012). In some instances, consumers tolerate water Hardness in excess of 500 mg/l. Depending on the interaction of other factors, such as pH and alkalinity, water with hardness above approximately 200 mg/l may cause scale deposition in the treatment works, distribution system and pipe work and tanks within buildings. Soft water, with a hardness of less than 100 mg/l, may, have a low buffering capacity and so be more corrosive for water pipes (WHO, 2011).
Nitrites
The highest mean nitrite value for protected springs was (0.015±0.017) mg/l at Okwakel and the lowest was (0.0055±0.001) mg/l at Omulubin (Table 3). All the three protected springs had values that were above the (UNBS, 1994) of 0 mg/l and below the WHO (2008) guidelines of 3 mg/l.
For boreholes, the highest mean nitrite value was (0.12±0.283) mg/l at Elgonia (BH1) and the lowest was (0.017±0.001) mg/l at Omatenga Rd (BH5) (Table 3). All the five boreholes sampled had Nitrite concentration which was above the UNBS (1994) limits and below the WHO (2008) limits. Generally, the findings indicated that there is a high Nitrite concentration in Boreholes as compared to the protected springs. The results agree with observation made by Emmanuel Bernard and Nurudeen Ayeni (2012). Nitrate can reach both surface water and groundwater as a consequence of agricultural activity (including excess application of inorganic nitrogenous fertilizers and manures), but groundwater concentrations generally show relatively slow changes. Some ground waters may also have nitrate contamination as a consequence of leaching from natural vegetation. In addition, the results of this study are not in agreement with the findings by Shivaraju., (2012) that the amount of nitrate in water indicates the biological contamination of water. This may not be true since in this study both the boreholes and protected springs had some concentration of nitrates with boreholes nitrate concentration higher than protected springs yet the former had no bacteriological contamination.
E- coli
E-coli bacterial counts in protected spring wells ranged between (0±0)/100 mg/l at Omulubin (SW2) and (22.5±3.536)/100 mg/l at Okwakel (SW3) (Table 3). The lowest value was within the required standards by WHO and UNBS but the values of protected springs of Odello and Okwakel were above the WHO and UNBS limits of 0/100 mg/l. The presence of this bacterium in spring water may be an indication of a recent contamination of the water source which may be attributed to anthropogenic activities such as open dumping of feaces by the communities.
The mean values of E-coli for boreholes were all at (0±0)/100 mg/l for all the five boreholes sampled that is Elgonia, Wiggins p/s, Kumi girls, Works and Matenga Rd (Table 3) and were therefore within permissible limits of drinking water by WHO and UNBS of 0/100 mg/l suggesting that borehole water is safe for human utilisation. The results for boreholes in this study agree with findings by Emmanuel Bernard and Nurudeen Ayeni (2012) that Water for human consumption must be free from organisms and chemical substances in concentration large enough to affect health. Also, the results obtained from this study showed that ground water sources (borehole water) is not as polluted as surface water (protected springs) this disagrees with Omari., Yeboah-Manu., (2012) that groundwater sources are as polluted as surface water sources. The presence of E. coli in the water samples collected from the ground and surface water sources emphasizes that there has been faecal contamination of the drinking water sources. E. coli is the only member of total coliform found exclusively in the faeces of humans and other animals, and its presence in water indicates not only recent faecal contamination of the water but also the possible presence of intestinal disease-causing bacteria, viruses, and protozoa (Omari., Yeboah-Manu., 2012). In addition, recent studies have recorded the occurrence of pathogenic strains of E. coli, which include E. coli O157:H7, and E. coli O111. The symptoms of illness associated with these strains are bloody and non-bloody diarrhoea that were accompanied by abdominal cramps (FAO/WHO, 2008). This means that there was the possibility of the occurrence and subsequent detection of these pathogenic strains in the water in the study area if a more sensitive method of microbial analysis had been employed in this study. Additionally, the detection of other bacterial species further demonstrates the level of faecal contamination of the ground and surface water sources in the study area.
The results of this study are in agreement with observations by Omari., Yeboah-Manu., (2012) that the detection of bacteria of faecal origin in surface water in the study area could be attributed to the fact that the protected springs have similar features: they lack proper physical barriers like concrete sanitary seals, concrete plinths, concrete aprons, well linings, sanitary covers, lockable sanitary lids which could prevent runoff containing human, animals and domestic wastes from contaminating the water sources. The WHO (2006) reported that groundwater is less vulnerable to contamination due to the barrier effect, and that once the protective barrier is breached direct contamination may occur. Chapman (1996) noted that due to the relatively slow movement of water through the ground, once polluted, a groundwater body could remain so for decades, or even centuries. Furthermore, the groundwater sources are constructed downhill and close to sanitation facilities as well as surface water. Consequently, runoff of human and domestic wastes and seepage of contaminants from the streams may pollute the water.
Total coliforms
The highest mean value for Total coliforms in the protected spring wells was (18.5±2.121)/100 mg/l at Odello (SW1) and the lowest was (1.5±0.707)/100 mg/l at Okwakel (SW3). All the three wells were far above the WHO and UNBS limits of 0/100 mg/l which may be an indication that there is poor sanitation and hygiene of the water catchment and water containers since presence of Total coliforms in water can give the general idea about the quality of water and health. The problem is compounded if a spring well is showing presence of both E-coli and Total coliforms which may be a health risk for the population that consumes this water together with the animals. The results of this study agree with findings by Bakas et al., (2012). In addition, in Kumi town council there are too many cattle from the surrounding communities grazing in the rangeland where the protected springs are located and the population of animals exceed the maximum for the size of the rangelands. Overgrazing is causing deforestation of the plants and vegetation. The animals uproot the plants and then step on the soil preventing possible development of new plants. This results in reducing retention of rainwater from the catchment areas. So the water is lost in the form of floods and torrents to the protected springs. This reduces the amount of water in aquifers and increases the concentration of pollutants into the water, leading to quality degradation.
All the boreholes had no T-coli with values of 0/100 mg/l that are within the WHO and UNBS limits of 0/100 mg/l which may be an indication of no recent contamination and that the general idea about the water quality as safe for human utilisation.
Distribution and source apportionment of contaminants in protected springs and borehole water.
Table 4: Spearman’s correlation (rs) matrix among selected Physicochemical parameters, Chemical and Bacteriological parameters in Protected spring water and borehole water of Kumi Town Council (n=3 and n=5)
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Correlation significant at P=0.05 (2-tailed)
Protected springs
Spearman’s (rs) correlation coefficients (significant at P=0.05) were evaluated as an Index of dependency among physicochemical, chemical and bacteriological variables. Turbidity was positively correlated with Iron (rs=0.995, at P=0.05), Nitrites (rs=0.999, at P=0.05) and E-coli (rs=0.982, at P=0.05) suggesting that turbidity is an indicator of contamination in water, but negatively correlated with Total coli forms (rs=0.542, at P=0.05) (Table 4).Turbidity increases with increased Iron concentration in water. pH was positively correlated with Hardness (rs=0.866,at P=0.05) and Total coli forms (rs=0.8403,at P=0.05) but pH was also negatively correlated with Iron (rs=0.0976,at P=0.05). Iron was positively correlated with Nitrite (rs=0.9902, at P=0.05) and E-coli (rs=0.9589, at P=0.05). Hardness was positively correlated with E-coli (rs=0.6547, at P=0.05).
Boreholes
pH had a strong correlation with Hardness (rs=0.7713, at P=0.05) and a negative correlation with Iron (rs=0.3874, at P=0.05) and Nitrite (rs=0.6667, at P=0.05).There was a weak positive correlation between Iron and Hardness (rs=0.2436, at P=0.05) but Iron was negatively correlated with Nitrite (rs=0.286, at P=0.05).Hardness was also negatively correlated with Nitrite (rs=0.708, at P=0.05)
CONCLUSION AND RECOMMENDATIONS
Conclusion
Protected spring water may not be of good quality if compared with the guidelines of WHO (2008) and UNBS(1994) in that all the three protected springs of Odello (SW1), Omulubin (SW2) and Okwakel (SW3) have a concentration of one or both parameters of bacteria that is E-coli and T-coli which could be attributed to poor hygiene and sanitation in the wells and in surrounding households as a result of improper disposal of human and animal wastes, poor maintenance and protection of the water catchment together with poor drainage channels for draining excess water. Also there is high concentration of Iron in this water which could be attributed to the age of the protected spring spouts and the vegetated catchment. Presence of these parameters may expose the communities in the town council depending directly on this water sources to water diseases.The major contaminant in boreholes was Iron whose concentration was far above the standards of the WHO (2008) and the UNBS (1994) and could in future increase the Turbidity measure that is a media (turbidity) for bacterial growth if not worked upon with urgency. The presence of Iron in water was attributed to the corrosion of the metallic pipes, the Iron containing underlying rock and the presence of mature trees near the water source. But even then, basing on the results of this study, borehole water was of better quality for human consumption.
Recommendations
All the water for domestic use should be boiled regularly to reduce the intake of bacteria through other uses where the users of water may undermine treatment of water or boiling. Coupled with this is the habit that drinking water is fetched from boreholes and water for other uses is collected from other sources could expose a population to water diseases. The district water office should conduct regular routine water quality analysis so as to keep track with the rate of water contamination and quality which then reduces public health risks and burden especially for women and children. Community involvement and awareness should be made priority especially as regards the maintenance of the hygiene in and around the water source while for those households who do not have well constructed latrines, they should be advised to erect it with immediate effect so as to reduce on the bacterial contamination of water which could expose society to cholera, typhoid and other water diseases. Use of protected springs to water animals may be controlled. The district water department should Conduct an assessment of soil quality for high iron level.
References
Amira AA, Yassir ME., (2011). Bacteriological quality of drinking water in Nyala, South Darfur, Sudan. Environ. Monit. Assess, 175: 37–43
Bakas et al., (2012) Bacteriological quality of the potable water supply sources in the area of Samothrace Island. International journal of environmental sciences Volume 2, No 1, ISSN 0976 – 4402
Chapman D., (1996) Water Quality Assessments. A guide to use of biota, sediments and water in environmental monitoring, 2nd (ED). E&FN Spon; 417
Emmanuel Bernard and Nurudeen Ayeni., (2012) Physicochemical analysis of groundwater samples of Bichi local government area of Kano state of Nigeria. ARPN journal of science and technology vol. 2, Special issue, ICESR ISSN 2225-7217
FAO/WHO., (2008) Microbiological hazards in fresh fruits and vegetables – Meeting Report.
Kazinja,V.,(2002).Sustainable Environmental Sanitation and Water services water treatment by solar energy. 28th WEDC conference, Kolkata (Calcutta),India
NDEFO et al., (2011) Physicochemical Evaluation of the Effects of Total Suspended Solids, Total Dissolved Solids and Total Hardness Concentrations on the Water Samples in Nsukka Town, Enugu State of Nigeria. Journal of American Science, 2011; 7(5)827.
Omari S., Yeboah-Manu D., (2012) The Study Of Bacterial Contamination Of Drinking Water Sources: A Case Study Of Mpraeso, Ghana. The Internet Journal of Microbiology. Volume 10 Number 1. DOI: 10.5580/2b06
Shanthi, C. and Ayomi, N., (2004).Impact of intensive cultivation on agro-well water quality in malsiripura region of kurunegala district. Water professional symposium.
Shalom Nwodo Chinedu et al., (2011) Assessment of water quality in Canaanland, Ota, Southwest Nigeria. Agriculture and biology journal of north America ISSN Print: 2151- 7517, ISSN Online: 2151-7525
Solomon Abera et al .,(2011) “Bacteriological analysis of drinking water sources” African Journal of Microbiology Research Vol. 5(18), pp. 2638-2641, African Journal of Microbiology Research Vol. 5(18), pp. 2638-2641.
Shivaraju H. P., (2012) Assessment of Physico-Chemical and Bacteriological Parameters of Drinking Water in Mysore City, India. International Journal of Research in Chemistry and Environment Vol. 2 Issue 1 January (44-53) ISSN 2248-9649
WHO (2001).Water quality, Guidelines, standards and health. Edited by Lorna Fewtral and Jamie Bartram. Published by IWA publishing, London , Uk.ISBN:1900222280117.
WHO, (2006) Guidelines for drinking-water quality: incorporating first addendum. Vol. 1, Recommendations, 3rd (ED); 1, 136, 143, 222, 282.
World Health Organisation: (2011) Drinking Water Standards and Health Advisories Office of Water U.S. Environmental Protection Agency Washington, DC.
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- Omuna Daniel (Author), Emmanuel Innocent Eniru (Author), 2016, Assessment of Portable Water Quality in Kumi Town Council, Eastern Uganda, Munich, GRIN Verlag, https://www.grin.com/document/350045